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Selective and Efficient Generation of ortho-Brominated para-Substituted Phenols in ACS-Grade Methanol.

ABSTRACT: The mono ortho-bromination of phenolic building blocks by NBS has been achieved in short reaction times (15-20 min) using ACS-grade methanol as a solvent. The reactions can be conducted on phenol, naphthol and biphenol substrates, giving yields of >86% on gram scale. Excellent selectivity for the desired mono ortho-brominated products is achieved in the presence of 10 mol % para-TsOH, and the reaction is shown to be tolerant of a range of substituents, including CH3, F, and NHBoc.

SUBMITTER: Georgiev D

PROVIDER: S-EPMC6274440 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Selective and Efficient Generation of ortho-Brominated para-Substituted Phenols in ACS-Grade Methanol.

Georgiev David D Saes Bartholomeus W H BW Johnston Heather J HJ Boys Sarah K SK Healy Alan A Hulme Alison N AN

Molecules (Basel, Switzerland) 20160113 1

The mono ortho-bromination of phenolic building blocks by NBS has been achieved in short reaction times (15-20 min) using ACS-grade methanol as a solvent. The reactions can be conducted on phenol, naphthol and biphenol substrates, giving yields of >86% on gram scale. Excellent selectivity for the desired mono ortho-brominated products is achieved in the presence of 10 mol % para-TsOH, and the reaction is shown to be tolerant of a range of substituents, including CH3, F, and NHBoc. ...[more]

PMID: 26771597

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